Are you keeping the factory fuel injection or planning to run a carburetor?
If you are keeping the fuel injection, you'll have to get a different converter with smaller flex plate pattern.
If you are going carbureted you can still get a converter with small diameter.
You could also get a cheap neutral balance flex plate that has the pattern you need, like sold at 440Source.com and some other vendors, then line everything up and transfer the weight from the Magnum flex plate to the same location on the neutral flex plate. You'd have to get it the same distance from crankshaft centerline and same position in regards to crank rotational position.
